Rainbow Science Materials

I happened to have all of these materials already on-hand both at home and in the classroom. That’s because I have a tendency to grab items when they’re on sale and keep them in my “stash”. Please tell me I’m not the only one who does this?

If you don’t have the exact same things listed below, that’s okay. See if you can borrow some ice cube trays from a teaching buddy. You don’t need both the squeeze bottles AND the eye droppers if you don’t have both. But they are definitely something I suggest having as part of your sensory and science materials if possible.

How to Make a Rainbow Science Invitation

Start out by making the scented baking soda “ice” cubes. For each of the colors (red, orange, yellow, green, blue, purple), I used the following “recipe”:

3/4 cup baking soda

2 tablespoons Jell-O powder

1/4 cup water

Food coloring (optional)

First, combine the baking soda and Jell-O powder in a bowl, and then add the water and mix.

To make the colors brighter, add a few drops of food coloring to the water before pouring it in. You can check out the picture above for a comparison of this rainbow science activity done with just Jell-O, as well as one done with added liquid watercolors. If you are doing this science activity with young children who might still put things in their mouths, I’d suggest leaving out the liquid watercolors (use food coloring instead or just leave it a little less colorful).

You will have a somewhat pasty mixture, so don’t be alarmed that it’s not a liquid. If it’s too thin it won’t set correctly.

Then use a spoon to add the mixture to the ice cube tray. I found that the above recipe gave me enough to fill one ice cube tray per color. If needed, tap the ice cube tray on your counter to ensure the mixture settles into the tray evenly.

Place the ice cube trays in the freezer.

Once they’re frozen through, remove from the freezer and get the rainbow science going immediately. I’d suggest arranging the cubes in rainbow order.

How the Kids Interact with the Rainbow Science Set-Up

Be sure to listen closely as they make observations about what they’re seeing. Ask open-ended questions to really get the children thinking. Encourage the children to experiment to find out the answers to their questions along the way.

Over the years, I’ve done this experiment a few times with kids at school and at home. Each and every time, the kids have asked for “more of that cool rainbow science!”

Here are some of the comments and questions I’ve heard:

“I can hear it fizzing! Can you hear it fizzing? Hey, what’s making the fizzing sound?”

“I can smell the vinegar right here [putting nose right by the bowl of vinegar], but I can’t smell it once it’s all mixed up there [pointing to the pan with the experiment in it].”

“It feels all cold and squishy now!”

“Why’s it all turning brown? Is it supposed to turn brown when all the colors are together like that?”

“Hey, I need a new pan please. With lots of vinegar. And a towel probably. I’m going to just use some of the colors. Maybe it won’t turn brown this time.”

Placing blue and yellow baking soda cubes in vinegar yielded green once the reaction was complete!

What Learning Takes Place with the Rainbow Science Activity?

This rainbow science experiment allows for an amazing amount of learning (for a variety of age groups)!

Here are some of the topics I’ve discussed with preschoolers and elementary-aged children:

Colors – tons of color identification, along with a discussion of the order of colors in a rainbow

Color mixing – put just two colors into a pan and let the children see what happens when the colors dissolve and mix together

The physics of rainbows – while this rainbow science experiment doesn’t delve directly into light and wavelengths, the question “why are the colors in the rainbow always in the same order?” may arise and lead to a great opportunity to discuss this (and plan for further science experiments)

Would your children enjoy our little rainbow science experiment? If you try it, I’d love to hear about how it goes!!

Preschool Lesson Plans You Should Check Out

Save time and get right to the playful learning with our printable lesson plan sets. Each set includes book suggestions, printable plans, over 30 learning activities (whole group, small group, and centers) related to the theme, and corresponding printables.

My mixture was a paste and I spooned it in an ice cube tray and put in the freezer over night. When I tried to take out the cubes they didnt budge and were squishy. Should I have left them longer? Now I have bags of squishy pasty baking soda with color.

I’d suggest using less water – did you try the exact measurements listed here? That’s what worked best for us. As for the bags of squishiness – maybe make a slushy rainbow in a large dish and still try the reactions! The kiddos will love that, too! Let me know what you end up trying and if I can help more!!!

Could you make this without the jell-o? Just mix baking soda, water, and food coloring? I realize it wouldn’t be scented then but do you think it would still work the same or is there something about the jell-o that is essential? Thanks for the great an fun idea!

I was thinking about doing this with a group of kids in my daycare class.. I was wondering would I be able to freeze them the night before and take them to class with me without them melting, or would the mixture be something I would have to mix at the daycare and freeze there?

When I did this with my class, I made them at home the night before. Then the next morning, I emptied the trays into Ziploc baggies and took them to school in lunchboxes with freezer packs. They went into the freezer at school and were just fine for using with the kids. 🙂

[…] Scented Rainbow Science from Fun-A-Day – Grab a few ingredients from the kitchen to set up this colorful, and deliciously-scented, science experiment. The kids will “ooooh!” and “aaaah!” as they jump right into testing chemical reactions. […]